An investigation on heavy particle dispersion in turbulent plane mixing layer by vortex-in-cell technique

Particle dispersion in mixing layer was investigated by numerical approach. Vortex-in-Cell technique was adopted to calculate velocity field, Lagrangian approach was used to find particle trajectories, and vorticity modified algorithm was introduced to present the interaction between flow and particles. By comparing numerical and experimental results, excellent agreement was found and the reliability of the present numerical procedure was verified. In the present results, we also observed that Stoke number descended downstream in mixing layer, so not just a single particle dispersive style existed in flow field; because the inertia of particle was larger than that of flow, particle streamwise mean velocity was smaller than flow streamwise mean velocity at the high speed side and was larger than that at the low speed side in the upstream, and particle streamwise mean velocity at the low speed side approached to flow streamwise mean velocity more faster than that at the high speed side; particle was more sensitive to streamwise velocity fluctuation than to transverse velocity fluctuation. Energy spectrum at downstream was calculated and the enstrophy cascade region with slope -3 at log scale was observed.